Vaporizing burner



Nov. 13, 1945. R. w. DE LANCEY 2,338,908

VAPORI Z ING BURNER Filed April 26, 1944 INVENTOR RALPH PM DELANCEY ATTORNEY Patented Nov. 13, 1945 'UNlTED STATES VAPORIZING BURNER Ralph W. De Lancey, Meriden, Conn, assignor to The Miller Company, Meriden, 001111., a corporation of Connecticut Application April 26, 1944, Serial No. 532,704

7 Claims.

The present invention relates to vaporizing burners, and is more particularly directed toward the provision of such burners with improved electrical preheating and ignition means.

When low grade oil fuel is supplied to a cold vaporizing type oil burner the dissipation of heat generated by an arc directed onto the vaporizer surface is so rapid that it is difiicult to secure ignition, I

The present invention contemplates providing the vaporizer or pot with an electrode which,

while electrically connected with the pot or vaporizer, is supported in such a way as to have a very poor thermal relation with the pot or vaporizer, whereby the heat caused by a spark playing on this electrode may cause the. electrode to be raised to a much higher temperature than would be the case if the spark played directly on the vaporizer or pot.

According to the present invention this vaporizer carried electrode, which may be a chrome steel disk, is supported just above the normal operating oil level and oil is brought opposite the upper electrode bycapillary action and wicking material.

Other and further objects will hereinafter appear as the description proceeds.

The accompanying drawing shows, for purposes of illustrating the present invention, two embodiments in which the invention may take form, it being understood that the drawing is illustrative of the invention rather than limiting the same.

In this drawing:

Figure 1 is a vertical sectional view through a vaporizing burner with parts in elevation;

Figure 2 is an enlarged sectional view illustrating the electrodes;

Figure 3 is a view similar to Figure 2 illustrating a modified form of construction;

Figure 4 is a fragmentary plan view of the lower electrode of Figure 2; and

Figure 5 is a wiring diagram.

The liquid fuel burner is constructed generally according to the showing in my patent application Serial No. 377,613, filed February 6, 1941. It has a vaporizer or pot Ill generally made of cast iron, a central air distributor H, flame spreader l2, housing l3 and a perforated sleeve M. The bottom of the housing is open as indicated at [5 and communicates with a blower (not shown). The fuel is supplied by a conduit or pipe indicated at l6, and is adapted to form an annular pool indicated at H. The normal operating level of the pool is indicated by the dotted insert 25 is not an oil tight joint, and, when the line I8, and the maximum oil level as determined by the metering valve setting is indicated at [9-,

The housing l3 of the burner is provided with an insulating support ZUfor an upper electrode 2! which extends down through the combustion chamber and terminates just above the upper surface of the vaporizer.

In the construction shown in Figures 1, 2 and4 the vaporizer it is provided with a lug 22 which is provided with a cylindrical hole 23 onasloping axis as indicated at 24 -2 4. The lower edge of the opening 23 is slightly below the maximum oil level 19 and. approximately at the normal operating level l8, as will be clear from Figure 2.

The opening 23 receives an insert 25 made of metal of low thermal conductivity. This insert is counterbored to have a'large diameteropening' 26 near its outer face, an intermediate diameter opening Z'I'and a small diameter openingZB. The seat 29 between the bores 21 and 28 accommodates a chrome steel disk 30, while the seat 3| between the bores 26 and 21 accommodates a steel disk 32. This disk 32 is preferably not imperforate, A wide variety of disks having an oil passage may be used. A simple construction is a disk with a central opening or perforation 33. Suitable noncombustible capillary material such as fibrous asbestos 34 is received between the disks 3!] and 32 and extends up through the opening 33. The fit between the diskp32 and the oil flows into the vaporizer, there is a tendency for some oil to seep down through the joint and wet the asbestos 34. As added insurance that the asbestos is wetted with the oil the disk 32 may be provided with a small bored hole indicated at 35.

In the modified form of construction shown in Figure 3 the vaporizer or pct 48 is counterbored as shown to receive a disk 4| similar to the disk 32 and a disk 42 similar to the disk 30, and asbestos 43 is inserted in a similar manner to that described.

When oil is admitted to the vaporizer or pot. i-t comes up to a level sufiiciently high to pass by capillary attraction to the asbestos and wet it, and is carried by the asbestos up through the hole in the disk or electrode '32 or 4|, so as to wet the asbestos just below the upper electrode 2!. The ignition current is supplied to the electrodes 2| and 32 by means of an ignition transformer T under the control of a suitable switch. Owing to the fact that the electrode 32 or 4| is in poor thermal relation with the massive vaporizer or pot the heat generated by the arc is able to elevate the temperature of the lower electrode to a much higher degree than it could raise the temperature of the massive vaporizer. This ele- 1 vation of temperature facilitates vaporization of the oil which has been transported by capillary attraction into the region of the arcing, and in this manner ignition is brought about under conditions where it would be extremely difficult and in some cases impossible to accomplish ignition by merely causing a spark to play on the vaporizer surface itself.

Owing to the high potentials employed in the sparking circuit the carbonaceous residues which will form in the space between the electrode and the vaporizer will be sufiicient to conduct the required current.

Since it is obvious that the invention may be embodied in other forms and constructions within the scope of the claims, I wish it to be understood that the particular forms shown are but a few of-these forms, and various modifications and change being possible, I do not otherwise limit myself in any way with respect thereto.

What is claimed is:

1. An oil burner comprising a vaporizing pot of heat conducting material having a sloping bottom with an upwardly opening recess in the upper surface thereof which recess is adjacent 119 but above the normal operating level of the oil in the pot, a fire resistant electrode secured in the recess in electrically conducting relation with the vaporizer pot, but in poor thermal conducting relation to the pot, the electrode having an oil passage therethroug an upper sparking electrode terminating adjacent the oil passage in the lower electrode, and capillary means for carrying oil from the pot surface adjacent the periphery of the lower electrode under it and up through the oil passage therein whereby the sparking action may heat the lower electrode above the temperature of the pot and the oil drawn up near the upper electrode may be va' porized and ignited by the spark.

2. An oil burner as claimed in claim 1, wherein the capillary meansincludes a hole through the lower. electrode and fibrous asbestos, the latter extending from the hole to the oil passage and up through the oil passage.

3. In an oil burner, a, vaporizing pot having a sloping bottom wall provided with an upwardly opening cavity above the normal operating level of the oil pool in the pot, a low heat conductivity metallic insert in the cavity, the insert being .counterbored to form a seat for a lower electrode,

a heat resistant electrode carried in the counterbore and substantially flush with the upper surface of the bottom wall of the vaporizer and having an oil passage, means includin capillary passages for causing oil to seep under the electrode, and asbestos fibres adapted to receive the capillary seepage and carry it up through the oil having a metallic vaporizing pot into which fuel is admitted to form a pool at a predetermined op.

erating level, the pot having a sloping bottom surface above said operatinglevel and connected to one side of a sparking transformer, and an upper electrode connected to the other side of the transformer, which improvement comprises a low thermal conductivity, metallic insert in the bottom wall of the pot above but adjacent they said operating level so as to be wetted by creepll'lg oil, the insert having an upwardly opening cavity, a metallic flame resistant electrode which closes the top of the cavity, and said upper electrode extending downwardly to within sparking distance from the second electrode whereby the latter may be heated by the spark between it and the first electrode to cause ignition of oil vapors.

6. The improvement claimed in claim 5, wherein the second electrode .has an oil passage and wherein asbestos fibres extend up into the passage from below it, the fibres being wetted by oil carried by capillary attraction from the oil pool.

7. The improvement claimed in claim 5, having a disk spaced from the second electrode, the second electrode having an oil passage under the first electrode, and having asbestos fibres between the disks and lower electrode and extending into the oil passage, the fibres being wetted by oil carried by capillary attraction from the oil pool.

RALPH W. DE LANCEY. 

